Endoscope apparatus

ABSTRACT

An endoscope apparatus including: an endoscope unit having: a lens units; a photographing unit for photographing an optical image picked up through the lens unit; and a lens unit driving motor for driving the lens unit for realizing at least one of a zoom function and a focus function; and a control unit having: an image processing circuit for processing an image signal output from the photographing unit, and for outputting the processed image signal to a monitor, wherein: at least one of the endoscope unit and the control unit comprises: a motor driving circuit for controlling the lens unit driving motor; and a motor control circuit for outputting a control signal that controls the motor driving circuit by detecting a switch signal generated by operation of a zoom switch or a focus switch.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a Continuation Application of PCT Application No. PCT/JP2005/10382, filed Jun. 7, 2005, which was not published under PCTArticle 21(2) in English.

This application is based upon and claims the benefit of priority fromthe prior Japanese Patent Application No. 2004-179693, filed Jun. 17,2004, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an endoscope apparatus.

2. Description of the Related Art

The conventional endoscope apparatus has a zoom control unit forcontrolling the enlargement and reduction in size of an optical imagethat is provided separately from a CCU (Camera Control Unit), asdisclosed, for example, by Japanese Patent Application Publication No.9-322566 and Japanese Patent Application Publication No. 8-336497.

Summary of the Invention

The endoscope apparatus according to the present invention includes anendoscope unit having a lens unit; a photographing unit forphotographing an optical image picked up through the lens unit, and alens unit driving motor for driving the lens unit for realizing at leastone of a zoom function and a focus function, and a control unit havingan image processing circuit for processing an image signal output fromthe photographing unit, and for outputting the processed image signal toa monitor, in which at least one of the endoscope unit and the controlunit comprises a motor driving circuit for controlling the lens unitdriving motor, and a motor control circuit for outputting a controlsignal that controls the motor driving circuit by detecting a switchsignal generated by operation of a zoom switch or a focus switch.

Also, the endoscope apparatus according to the present inventioncomprises an endoscope unit having a lens unit, a photographing unit forphotographing an optical image picked up through the lens unit, and alens unit driving motor for driving the lens unit for realizing at leastone of a zoom function and a focus function, and a control unit havingan image processing circuit for processing an image signal output fromthe photographing unit, and for outputting the processed image signal toa monitor, a motor driving circuit for controlling the lens unit drivingmotor, and a motor control circuit for outputting a control signal thatcontrols the motor driving circuit by detecting a switch signalgenerated by operation of a zoom switch or a focus switch.

Also, the endoscope apparatus according to the present inventioncomprises an endoscope unit having a lens unit, a photographing unit forphotographing an optical image picked up through the lens unit, and alens unit driving motor for driving the lens unit for realizing at leastone of a zoom function and a focus function a motor driving circuit forcontrolling the lens unit driving motor, and a motor control circuit foroutputting a control signal that controls the motor driving circuit bydetecting a switch signal generated by operation of a zoom switch or afocus switch and a control unit having an image processing circuit forprocessing an image signal output from the photographing unit, and foroutputting the processed image signal to a monitor.

Further, in the above endoscope apparatus, the control unit furthercomprises an operation unit, and a control circuit for providing, to themotor control circuit, a control signal for controlling the motordriving circuit on the basis of a switch signal generated by operationof the operation unit and a switch signal generated by operation of thezoom switch or the focus switch.

Also, in the above endoscope apparatus, the endoscope unit furthercomprises a determination information notification unit for notifyingdetermination information used for the determination of whether theendoscope unit has a zoom function and a focus function, and the controlunit further comprises a control unit for controlling operation of themotor driving circuit and the motor control circuit on the basis of thedetermination information notified by the determination informationnotification unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a configuration of an endoscope system to which the presentinvention can be applied;

FIG. 2 is a block diagram that shows a configuration of the endoscopeapparatus according to the first embodiment of the present inventionwith a connected camera head that has a zoom function and a focusfunction;

FIG. 3 shows the waveform of a motor driving voltage (voltage driving);

FIG. 4 is a block diagram that shows a configuration of the endoscopeapparatus according to the first embodiment of the present inventionwith a connected camera head that does not have a zoom function or afocus functions;

FIG. 5 is a block diagram that shows a configuration of the endoscopeapparatus according to the second embodiment of the present inventionwith a connected camera head that has a zoom function and a focusfunction;

FIG. 6 shows the configuration of the motor control circuit 27 accordingto the second embodiment of the present invention;

FIG. 7 is a block diagram that shows a configuration of the endoscopeapparatus according to the second embodiment of the present inventionwith a connected camera head that does not have a zoom function or afocus function;

FIG. 8 is a block diagram that shows a configuration of the endoscopeapparatus according to a third embodiment of the present invention witha camera head connected that has a zoom function and a focus function;

FIG. 9 shows a configuration of a motor control circuit 27-1 accordingto the third embodiment of the present invention;

FIGS. 10A through 10D show bit sequences and bit contents of serial dataSD1 and SD2; and

FIG. 11 is a block diagram that shows a configuration of the endoscopeapparatus according to the third embodiment of the present inventionwith a connected camera head that does not have a zoom function or afocus function.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the above conventional technique, the zoom control unit is providedseparately from the CCU, and this has prevented the size of endoscopeapparatuses from being reduced.

An endoscope apparatus according to the present invention realizes sizereduction by integrating a drive/control system used for zoom controland focus control into an existing circuit.

Hereinafter, embodiments of the present invention will be explained indetail by referring to the drawings.

FIG. 1 shows a configuration of an endoscope system to which the presentinvention can be applied. As an endoscope unit including a photographingdevice such as a CCD or the like, an optical endoscope 2 inserted into acoelum of a patient is connected to a camera head 3. As a control unitincluding a CPU and an image signal processing circuit, the camera head3 is connected to a CCU (Camera Control Unit) 4. The camera head 3 isprovided with a zoom switch (hereinafter, referred to as “zoomSW”) 25and a focus switch (hereinafter, referred to as “focus SW”) 26. The CCU4 is connected to a display monitor 5. A light source device 6 isconnected through a light guide 7 to the optical endoscope 2. Note thata video scope in which the optical endoscope 2, the camera head 3, andthe light guide 7 are integrated may be employed as a configuration ofthe present invention.

Note also that a videoscope in which a camera head and a light guide areintegrated together with a rigid endoscope, a flexible endoscope, or anoptical endoscope may be employed as the optical endoscope 2.

First Embodiment

FIG. 2 is a block diagram that shows a configuration of an endoscopeapparatus according to the first embodiment of the present inventionwhen a camera head having a zoom function and a focus function isconnected. The camera head 3 includes a lens unit 10, a CCD(photographing device) 11, a TG (Timing Generator) 13, a zoom motor 21,a focus motor 22, a zoom position detection unit 23, a focus positiondetection unit 24, the zoom SW 25, the focus SW 26, and an ID storageunit 29.

The lens unit 10 includes a zoom lens and a focus lens. Information usedfor discriminating types of camera heads (e.g., whether or not thecamera unit has zoom and focus functions) is stored in the ID storageunit 29.

The CCU 4 includes an image processing circuit 12, an SSG(Synchronization Signal Generator) 14, a clock oscillator 15, a dividercircuit 16, a motor driving circuit 18, a CPU 17, a motor power circuit19, and a control power circuit 20.

When the endoscope apparatus begins operation, the camera head 3 isconnected to the CCU 4 first. Then, the ID storage unit 29 in the camerahead 3 sends an ID signal of the camera head 29 to the CPU 17 of the CCU4.

The CPU 17 determines whether the camera head 3 that is currentlyconnected to the CCU 4 is a camera head for zooming/focusing on thebasis of the ID signal. When it is determined that the camera head 3that is currently connected to the CCU 4 is a camera head forzooming/focusing (i.e., the case shown in FIG. 2), the processes beloware executed.

An observation image of observation target tissue is picked up by anoptical endoscope 1 inserted into the body of a patient and isphotographed by the CCD 11. An image signal from the CCD 11 is inputinto the image processing circuit 12 and is subjected to a prescribedimage process. The signal that has been subjected to the image processis sent to the display monitor 5 (FIG. 1) as a display signal and isdisplayed as a subject image 8.

The clock oscillator 15 generates a clock signal CLK having a prescribedfrequency. This clock signal CLK is sent to the SSG 14 where ahorizontal synchronization signal (HSYNC), a vertical synchronizationsignal (VSYNC), and synchronization signals of other types aregenerated. The HSYNC and the VSYNC are sent to the timing generator (TG)13 together with the CLK, the image processing circuit 12, and the CPU17. The TG 13 generates a signal that determines the timing at which theCCD 11 photographs the image.

When a user operates the zoom SW 25, a TELE or WIDE switch signal issent to the CPU 17. The CPU 17 sends a control signal that causes thezoom lens to operate in accordance with the signal to the motor drivingcircuit 18. The motor driving circuit 18 operates in accordance with thesignal obtained by dividing the CLK from the clock oscillator 15 byusing the divider circuit 16. The motor driving circuit 18 generatessignals ZA, ZB, ZA (inverted), and ZB (inverted) that drive the zoommotor 21 in accordance with the control signal from the CPU 17. Herein,ZA is a signal represented by phase A of a waveform of a zoom motordriving voltage, ZB is a signal represented by phase B (shifted fromphase A by ¼ cycle) of the waveform of the zoom motor driving voltage,ZA (inverted) is a signal obtained by inverting ZA, and ZB (inverted) isa signal obtained by inverting ZB. An example of phase A, phase B, phaseA (inverted), and phase B (inverted) is shown in FIG. 3.

The zoom motor 21 moves the zoom lens in the lens unit 10 in the TELEdirection or in the WIDE direction on the basis of these signals. Whenthe position of the zoom lens is detected by the zoom position detectionunit 23 comprising a photo interrupter or the like, the positioninformation is provided to the CPU 17 as a PIZ signal by the zoomposition detection unit 23. Thereby, the CPU 17 can move the zoom lensto desired positions.

When the user operates the focus SW 26, a switch signal of NEAR or FARis sent to the CPU 17. The CPU 17 sends a control signal that causes thezoom lens to operate in accordance with the signal to the motor drivingcircuit 18. The motor driving circuit 18 generates signals FA, FB, FA(inverted), and FB (inverted) to drive the focus motor 22 in accordancewith the control signal from the CPU 17. FA is a signal represented byphase A of a waveform of a focus motor driving voltage, FB is a signalrepresented by phase B (shifted from phase A by ¼ cycle) of the waveformof the focus motor driving voltage, FA (inverted) is a signal obtainedby inverting FA, and FB (inverted) is a signal obtained by inverting FB.An example of phase A, phase B, phase A (inverted), and phase B(inverted) is shown in FIG. 3.

The focus motor 22 moves the focus lens in the lens unit 10 to bothproximal and distal positions in accordance with the signals. When theposition of the focus lens is detected by the focus position detectionunit 24 that includes a photo interrupter or the like, the positioninformation is provided to the CPU 17 as a PIF signal by the focusposition detection unit 24. Thereby, the CPU 17 can move the focus lensto a focus position.

When the camera head having zoom/focus functions is detected as above,the CPU 17 controls the control power circuit 20, the motor powercircuit 19, and the motor driving circuit 18 in order to control thezoom/focus operations.

FIG. 4 is a block diagram that shows a configuration of an endoscopeapparatus according to the first embodiment of the present inventionwith a camera head connected that does not have a zoom function or focusfunctions. FIG. 2 explains the case in which the camera head has a zoomfunction and a focus function connected. In FIG. 4, the case isexplained in which a camera head that does not have a zoom function or afocus function is connected.

When the endoscope apparatus operates, the camera head 3 is firstconnected to the CCU 4. Then, the ID storage unit 29 in the camera head3 sends an ID signal for the camera head 29 to the CPU 17 of the CCU 4.

The CPU 17 determines whether or not the camera head 3 that is currentlyconnected to the CCU 4 is a camera head for zooming/focusing on thebasis of the ID signal. When it is determined that the camera head 3that is currently connected to the CCU 4 is not a camera head forzooming/focusing (i.e., the case in FIG. 4), the CPU 17 does not send acontrol signal to the motor driving circuit 18. Also, the CPU 17 sendsthe control signal to the motor power circuit 19 and control powercircuit 20 in order to shut down the power of the motor power circuit 19and control power circuit 20. Thereby, wastes of power can be reduced.

Signal lines of input signals (PIZ, PIF, TELE, WIDE, NEAR, and FAR) fromthe camera head 3 to the CCU 4 are fixed at a Low level (GND fix). Inaddition, there is no signal line of output signals (ZA, ZB, ZA(inverted), ZB (inverted), FA, FB, FA (inverted), and FB (inverted))from the CCU 4 to the camera head 3 on the camera head side, and theyare opened.

According to the first embodiment of the present invention, thedrive/control system for the zoom control and the focus control isintegrated into the CCU 4 so that the size of the entire electronicendoscope apparatus can be reduced. Also, because the drive/controlsystem for the zoom control and the focus control is integrated into theCCU 4, the number of components operated by a user can be reduced sothat the use of the electronic endoscope apparatus becomes moreuser-friendly. Further, there can be a reduction in the unnecessaryconsumption (waste) of electric power of the motor power circuit 19 andthe control power circuit 20.

Second Embodiment

FIG. 5 is a block diagram that shows a configuration of the endoscopeapparatus according to the second embodiment of the present inventionwith a camera head connected that has a zoom function and a focusfunction is. In this embodiment, the case is explained in which themotor driving circuit 18, a motor control circuit 27, and the dividercircuit 16 explained in FIG. 2 are included in the camera head 3.

When the endoscope apparatus operates, the camera head 3 is firstconnected to the CCU 4. Then, as with the first embodiment, it isdetermined that the camera head that is currently connected has a zoomfunction and a focus function.

FIG. 6 shows a configuration of the motor control circuit 27 accordingto the second embodiment in which a motor driving circuit control unit51 and an SW signal/position detection unit 52 are included. The SWsignal/position detection unit 52 detects a switch signal generated byoperation of the zoom SW 25 or the focus SW 26. Also, the SWsignal/position detection unit 52 receives the PIZ signal from the zoomposition detection unit 23 and the PIF signal from the focus positiondetection unit 24, and sends an instruction signal to the motor drivingcircuit control unit 51. Receiving the instruction signal from the SWsignal/position detection unit 52, the motor driving circuit controlunit 51 sends various control signals to the motor driving circuit 18.

FIG. 7 is a block diagram that shows a configuration of the endoscopeapparatus according to the second embodiment of the present inventionwith a camera head connected that does not have a zoom function or afocus function. When the endoscope apparatus operates, the camera head 3is connected to the CCU 4. Then, as with the first embodiment, it isdetermined that the camera head that is currently connected is a camerahead that does not have a zoom function or a focus function. Then, theCPU 17 sends the control signal to the motor power circuit 19 and thecontrol power circuit 20 in order to shut down the power of the motorpower circuit 19 and the control power circuit 20. Thereby, there can bea reduction in the unnecessary consumption (waste) of power.

According to the second embodiment, the drive/control system for thezoom control and the focus control is included in the camera head 3 sothat the size of the apparatus can be reduced and the total number ofconnector pins (the number of signal lines) between the camera head 3and the CCU 4 can be greatly reduced. The number of signal lines betweenthe camera head 3 and the CCU 4 is actually two: one for the motor powercircuit 19 and the other for the control power circuit 20. Also, theunnecessary consumption (waste) of power of the motor power circuit 19and the control power circuit 20 can be reduced.

Third Embodiment

FIG. 8 is a block diagram that shows a configuration of the endoscopeapparatus according to the third embodiment of the present inventionwith a camera head connected that has a zoom function and a focusfunction. When the endoscope apparatus operates, the camera head 3 isfirst connected to the CCU 4. Then, as with the first embodiment, theCPU 17 determines that the camera head 3 that is currently connected hasa zoom function and a focus function on the basis of the informationread from the ID information storage unit.

In this embodiment, as in the second embodiment, the motor drivingcircuit 18, the motor control circuit 27, and the divider circuit 16 areincluded in the camera head 3. Also, wiring is provided such thatbidirectional serial communications can be conducted between a motorcontrol circuit 27-1 in the camera head 3 and the CPU 17 of the CCU 4.Further, a keyboard 28 whose keys can act as switches for givinginstructions for zoom and focus operations is connected to the cup 17.

FIG. 9 shows a configuration of the motor control circuit 27-1 in thethird embodiment comprising the motor driving circuit control unit 51,the SW signal/position detection unit 52, a serial/parallel conversionunit 54, and a serial data generation unit 53.

In the third embodiment, the CPU 17 receives not only the switch signalgenerated by operation of the zoom SW 25 or the focus SW 26, but also aswitch signal generated by operation of the keyboard 28, such that thezoom operation and the focus operation can be controlled through thekeyboard 28.

Specifically, the switch signals (TELE and WIDE) generated by operationof the zoom SW 25 of the camera head 25, the switch signals (NEAR andFAR) generated by operation of the focus SW 26, the PIZ signal from thezoom position detection unit 23, and the PIF signal from the focusposition detection unit 24 are input into the serial data generationunit 53 and also into the CPU 17 as serial data SD1. FIG. 10A shows abit sequence of the serial data SD1. FIG. 10B shows the contents of thebits.

The CPU 17 of the CCU 4 generates a signal as serial data SD2 forcontrolling the motor driving circuit 18 on the basis of the data SD1and the switch signal generated by operation of the keyboard 28. FIG.10C shows a bit sequence of the serial data SD2. FIG. 10D shows thecontents of the bits.

The serial/parallel conversion unit 54 receives the serial data SD2 fromthe CPU 17 and converts it into parallel signals of TELE1, WIDE1, NEAR1,and FAR1. The SW signal/position detection unit 52 detects theseparallel signals and sends an instruction signal to the motor drivingcircuit control unit 51. Receiving the instruction signal from the SWsignal/position detection unit 52, the motor driving circuit controlunit 51 sends various control signals to the motor driving circuit 18.

A superimposing circuit 30 is used for superimposing current zoommagnification information and a current focus position onto an endoscopyimage. The superimposing circuit 30 includes a selector by which animage signal output from the image processing circuit 12 and a signalincluding the zoom magnification information and the current positionoutput from the CPU 17 are switched to be output as a monitor signal.

FIG. 11 is a block diagram for showing a configuration of the endoscopeapparatus according to the third embodiment of the present inventionwith a camera head connected that does not have a zoom function or afocus function. When the endoscope apparatus operates, the camera head 3is first connected to the CCU 4. Then, as with the first embodiment, theCPU 17 determines that the camera head 3 that is currently connected isa camera head that does not have a zoom function or a focus function onthe basis of the information read from the ID information storage unit.Next, the CPU 17 sends the control signal to the motor power circuit 19and the control power circuit 20 in order to shut down the power of themotor power circuit 19 and control power circuit 20. Thereby, theunnecessary consumption (waste) of power can be reduced.

According to the third embodiment, in addition to the effects of thesecond embodiment, it is possible to control the zoom operation and thefocus operation through peripheral devices such as the keyboard 28 andthe like. Further, the superimposing circuit 30 that is in sequenceafter the image processing circuit 12 can superimpose, onto the imagesignal from the image processing circuit 12, the current zoommagnification information and the current focus position obtained fromthe PIZ signal and the PIF signal sent to the CPU 17. The superimposingcircuit 30 does this in order to display the image with its current zoommagnification information and the current focus position on the displaymonitor 5.

Additionally, the ID information is used to determine the type ofconnected camera head in the first through third embodiments. Notehowever that the scope of the present invention is not limited to theseembodiments, and the type of camera head may, for example, be determinedby detecting the value of resistance that is set for each type of camerahead.

As described above, according to the present invention, thedrive/control system for the control of the zoom operation and the focusoperation is integrated into an existing circuit; accordingly, the sizeof the endoscope apparatus can be reduced.

1. An endoscope apparatus including: an endoscope unit having: a lensunit; a photographing unit for photographing an optical image picked upthrough the lens unit; and a lens unit driving motor for driving thelens unit for realizing at least one of a zoom function and a focusfunction; and a control unit having: an image processing circuit forprocessing an image signal output from the photographing unit, and foroutputting the processed image signal to a monitor, wherein: at leastone of the endoscope unit and the control unit comprises: a motordriving circuit for controlling the lens unit driving motor; and a motorcontrol circuit for outputting a control signal that controls the motordriving circuit by detecting a switch signal generated by operation of azoom switch or a focus switch.
 2. An endoscope apparatus, comprising: anendoscope unit having: a lens unit; a photographing unit forphotographing an optical image picked up through the lens unit; and alens unit driving motor for driving the lens unit for realizing at leastone of a zoom function and a focus function; and a control unit having:an image processing circuit for processing an image signal output fromthe photographing unit and for outputting the processed image signal toa monitor; a motor driving circuit for controlling the lens unit drivingmotor; and a motor control circuit for outputting a control signal thatcontrols the motor driving circuit by detecting a switch signalgenerated by operation of a zoom switch or a focus switch.
 3. Anendoscope apparatus, comprising: an endoscope unit having: a lens unit;a photographing unit for photographing an optical image picked upthrough the lens unit; a lens unit driving motor for driving the lensunit for realizing at least one of a zoom function and a focus function;a motor driving circuit for controlling the lens unit driving motor; anda motor control circuit for outputting a control signal that controlsthe motor driving circuit by detecting a switch signal generated byoperation of a zoom switch or a focus switch; and a control unit having:an image processing circuit for processing an image signal output fromthe photographing unit and for outputting the processed image signal toa monitor.
 4. The endoscope apparatus according to claim 3, wherein: thecontrol unit further comprises: an operation unit; and a control circuitfor providing, to the motor control circuit, a control signal forcontrolling the motor driving circuit on the basis of a switch signalgenerated by operation of the operation unit and a switch signalgenerated by operation of the zoom switch or the focus switch.
 5. Theendoscope apparatus according to claim 1, wherein: the endoscope unitfurther comprises: a determination information notification unit fornotifying determination information used for the determination ofwhether or not the endoscope unit has a zoom function and a focusfunction; and the control unit further comprises: a control unit forcontrolling the operation of the motor driving circuit and the motorcontrol circuit on the basis of the determination information notifiedby the determination information notification unit.
 6. The endoscopeapparatus according to claim 2, wherein: the endoscope unit furthercomprises: a determination information notification unit for notifyingdetermination information used for the determination of whether or notthe endoscope unit has a zoom function and a focus function; and thecontrol unit further comprises: a control unit for controlling theoperation of the motor driving circuit and the motor control circuit onthe basis of the determination information notified by the determinationinformation notification unit.
 7. The endoscope apparatus according toclaim 3, wherein: the endoscope unit further comprises: a determinationinformation notification unit for notifying determination informationused for the determination of whether or not the endoscope unit has azoom function and a focus function; and the control unit furthercomprises: a control unit for controlling the operation of the motordriving circuit and the motor control circuit on the basis of thedetermination information notified by the determination informationnotification unit.